The long-term objective of this research is to identify genetic and environmental factors in the etiology of drug abuse, leading to rational intervention and preventative measures based on biologic and psychosocial factors and their interaction. The specific aims of the project are to study in an adoption design genetic factors making for high risk of drug abuse (alcohol abuse and antisocial personality in biologic parents) as well as a wide variety of environmental factors in the adoptive environment and their interaction. A sample of adoptees, separated at birth from biologic family and placed with non-relatives will be personally interviewed with the DIS as adults to determine drug abuse, other relevant psychiatric conditions as alcohol abuse and antisocial personality. One hundred adoptees will come from high risk backgrounds (50 from biologic parents with alcohol abuse/dependency and 50 from antisocial parent) . Biologic parents will be diagnosed from hospital records. These hundred high risk adoptees will be age and sex matched to a control group of one hundred adoptees whose biologic parents have no evidence of hospital treatment for alcoholism or antisocial personality and whose adoption agency records do not indicate behavioral or psychiatric problems. Adoptive parents will be interviewed to provide further behavioral information about the adoptee and his/her environment. Environmental factors will be measured by three structured interviews administered to adoptive parents and/or adoptee. Interviews will be conducted by research personnel who are blind to biologic risk factors. Correlations between genetic and environmental factors and outcome variables of substance abuse and antisocial personality will be measured in log-linear models, and with logistic regression.